The present disclosure relates to a wind power generation unit, a wind farm which improves the degree of agglomeration, and arrangement structure and control method of the same, and more particularly, to a wind power generation unit, a wind farm, and arrangement structure and control method of the same, which facilitate arrangement of more wind power generation units in the same area by minimizing vortex interaction between the wind power generation units.
In wind power generation, a power generation facility converts kinetic energy of wind into a rotational energy of blades and produces electricity by operating an electric generator inside a nacelle.
Referring to FIG. 1, a wind farm includes a plurality of wind power generation units which rotate in the clockwise direction and are arranged at sufficient distances from each other in order to avoid a mutual interference. Therefore, a task in creating the wind farm including dozens or hundreds of wind power generation units is to secure enough land to arrange the wind power generation units at the sufficient distances from each other.
It can be considered to narrow the distance between the wind power generation units in order to increase power capacity per land unit, but it may cause a vibration of the blades due to vortex interaction generated by rotation of the blades of each wind power generation unit. Because the lifespan of the wind power generator is reduced due to such a vibration, in reality, there is a limitation in narrowing the distance between the wind power generation units.
In more detail, between the wind power generation units neighboring in a longitudinal direction as shown in FIG. 2, a rear vortex moves in the opposite direction to the rotational direction of the blades while wind passing the blades collides with the blades. That is, in the case of A1 of FIG. 2, while the blades rotate in the clockwise direction, rear vortex is generated in the counterclockwise direction and is transferred to B2.
FIG. 3 illustrates an influence of the rear vortex more concretely. As shown in FIG. 3, the wind power generation units of A1, B1 and C1 are all arranged in the longitudinal direction and all rotate in the clockwise direction. In this instance, all of the wind power generation units generate the rear vortex in the counterclockwise direction, and the rear vortex are overlapped and gradually amplified from A1 toward B1 and C1. As described above, in the conventional wind farm, the wind power generation units are arranged in the longitudinal direction at a sufficient distance from each other to avoid such an influence of the rear vortex in the longitudinal direction.
Meanwhile, between wind power generation units which are adjacent to one another in a transversal direction, a vortex is generated by centrifugal force generated by rotation of blade tips of each wind power generation unit. That is, in FIG. 2, a vortex directing downward is generated at the right side of A1 but a vortex directing upward is generated at the left side of A2. Therefore, mutual collision of the vortexes causes a vibration of the blades.
In more detail, conventionally, in case that a plurality of wind power generation units are installed, a vertical interval which is about seven times the rotor diameter must be maintained in order to minimize an efficiency drop of the wind power generation units installed at the rear by a slipstream flow generated by the wind power generation units installed at the front, and a transversal interval which is about three times the rotor diameter must be maintained in order to minimize an efficiency drop of wind power generation units by a vortex interaction generated by the wind power generation units installed laterally, and hence, there is a limitation in increasing the degree of agglomeration of the wind power generation units.